We know that umpires call different strike zones. The strike zone varies from night to night, and some pitchers benefit from a larger strike zone than others. Just ask Mike Leake which side of that he was on Sunday. As I mentioned in the Game Thread Friday night, the folks at The Hardball Times presented new illustrations from pitch f/x data last week that showed the strike zone changes size based on pitch count.
Umpires expand their strike zone on 3-0 pitches and shrink their strike zones on 0-2 pitches. TheyÃ¢â‚¬â„¢ve estimated a 3-0 count has on average a 50% larger strike zone being called than an 0-2 pitch. In fact, they illustrate that the correlation between strike zone size and pitch count exists for 2-0 and 0-1 pitch counts also. On average, the strike zone is wider in a hitterÃ¢â‚¬â„¢s count and narrower in a pitchers count.
I wouldn’t think that this is something intentionally done on the part of the umpires, but it would seem, at least subconsciously, that the umpires want to see the outcome of the game based on the batter swinging the bat.